[Towertalk] There are no dumb questions on Tower Talk, only dumb answerrs!

[Jim White]

...........somebody ages ago pointed out that on one install they had
improved (decreased) their feedline loss by using some better hard line for
part of the run - as it turned out the adding of two barrel connectors (4
connections) probably offset all of his gains!

It is a pain but - the fewer splices the less deamons creep in - yes it
makes it tough to do maintennance, etc....BUT

This past weekend we ran Multi-Multi in the WPX contest....as the contest
was getting ready to start the 40 meter operator (Kevin, N4KM) started to
find himself a frequency - at this point every band reported they were being
torn up by his transmitting - for the first two hours of the contest Kevin
worked on tracking down the problem - we swapped feedlines in the shack -
eliminated coax switches, etc.....when we put the cantenna at the base of
the tower the 40 meter beam was on all was well, this is where the hardline
ended and 213 flex went from there to the wall through........no trashing
was occurring, so....

This meant the problem was after the next splice point which would have been
at the top of the tower about 135 feet up.....

We made do with a vertical to make some contacts on 40 the first night and
Kevin kept his butt in the chair despite being challenged antenna wise...

The next day a part time operator showed up and he volunteered his help in
any way he could for our mm effort - I told him to be honest I really
thought we could best use his help at climbing up to the top and possibly
swapping out the coax for the 40 meter beam....we were ready to sacrifice
the 160 feedline to do this.

He climbed up and inspected the splice at the end of the hardline - cutting
away the tape, etc to get at the barrel....he took another barrel up with
him and swapped it for the one that was in there...we tried the beam after
this relatively a straight forward swap and VOILA the QRM was gone - the 40
meter beam was back in our arsenal.

Two things:

A) As this thread was started with a question regarding splicing in coax -
think twice....

B) Be thankful we have such a great hobby that a friend will come over climb
your tower and replace a barrel and then operate for a few hours at over
+100 per hour....he then thanks you for the chance to help out the operation
gets in his car and goes to a multi-single to help them fatten up their
numbers....

Amazing, huh....like I said  - splices are two edged swords - they can be
good and they can be your nemesis!

Oh yes, the friend who climbed the tower and then proceeded to run like
crazy on 15 and 20 meters as a relief operator for our WC4E operation...and
then drove to multi-single N4TO was none other than K1TO - WRTC two time
co-champion....we sure are glad he is with the  Florida Contest Group!

Thanks, Dan!

..THIS IS a great hobby!

Jim, K4OJ

[there is no truth to the rumour that I told Dan he had to climb the tower
before he could operate!]


----- Original Message -----
From: "Bruce Makas" <k1my@msn.com>
To: "Towertalk submital" <towertalk@contesting.com>
Sent: Tuesday, May 28, 2002 6:54 PM
Subject: [Towertalk] Really dumb question on coax


> One of my towers is 270 feet from the entry point (where all the switching
> and grounding takes place) to the house. I have a 200 foot length of
LMR600
> (loss of 0.42 db per 100ft @ 30 mhz) and lots of Beldon 9913FX (0.8 db
loss
> per 100 ft).
>
> My question is whether I'm better off using 270 feet of the Beldon or 200
> feet of the LMR and 70 feet of the Beldon connected with PL259's and a
> barrel connector.
>
> 270 x 0.8 = 2.16 db loss
> 200 x .42 + 70 x .8 = 1.40 db plus loss of connectors
>
> I know that I can make a watertight joint so feedline loss should be my
only
> concern. I know that it is close and that I probably can't tell the
> difference but which way is actually better?
>
> Thanks,  Bruce K1MY
>
>
> _______________________________________________
> Towertalk mailing list
> Towertalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk